(1) Field of the Invention
The present invention relates to a composite wear-resistant member that has high hardness and density and contains super-hard particles (e.g. diamond particles or cubic boron nitride (cBN) particles) and, more particularly, to composite wear-resistant member that is excellent in heat and pressure shock-resistant characteristics, and a method of manufacturing the same.
(2) Description of related art
Hard metals are generally used for wear-resistant tools as in petroleum drilling due to high toughness and wear resistance. Recently, composite materials (e.g. polycrystalline diamond compacts (PDC)) joining a diamond composite material to the hard metal under very high pressure at high temperature have been frequently used.
These sintered compacts containing diamond particles are manufactured under very high pressure at high temperature. However, a method of manufacturing a sintered compact of diamond, tungsten carbide (WC), and ferrous metal under low pressure rather than high pressure has recently studied (JP-B2-3309897 and WO2006-080302A1 (U.S. Pat. No. 7,637,981)).
However, all the diamond composite materials whether the PDCs manufactured under very high pressure or the diamond composite materials manufactured under low pressure have a fundamental problem in that cracks or defects may occur due to shock caused by heat or pressure.
To overcome this problem, various attempts have been made (U.S. Pat. Nos. 5,119,714, 4,604,106, 4,525,178, 4,694,918 and JP-A-9-194909). Although some effects are recognized, the inventions disclosed in these documents do not yet provide a fundamental means that has many countermeasures against the stress of joints and prevents generation and propagation of distortion caused by shock by reinforcing the material itself.